Metastasis question... 2

I've illustrated the questions I've posed in my previous post, "Metastasis question..." (Figure 1).

In A1 and A2, we see a single cancer cell extravasating (this is how I portrayed metastasis in "Prologue - the metastacizing cell").

B1 and B2 shows an aggregation of cancer cells exiting into a capillary as a single unit.

If neither of these two options are correct, is it possible that 1) singular cells extravasate and rejoin in a larger vessel; or 2) the aggregation exits into a large diameter vessel (in which case another question - how many layers thick is the vessel)? Also, what is the diameter of these cancer cells, and how large are the lumens into which they extravasate?

FIGURE 1.